The main goal of the contract is to measure LTL in Womens Health Initiative - Long Life Study (WHI-LLS) participants at two time points, approximately 15 years apart in order to assess LTL dynamics (LTL and its age-dependent attrition) in relation to incident coronary heart disease (CHD) events and mortality. The central question the contractor would like to answer is as follows: Can knowledge about LTL improve classification of an elderly womans risk of CHD and early mortality? Answering this question is consistent with the overall goal of the LLS which is to support studies of factors associated with healthy aging and examine the changing levels of intermediate markers of cardiovascular disease (CVD) risk on subsequent clinical events. To this end, the contractor will use LTL measurements to test five specific aims that mechanistically link its dynamics to atherosclerotic CVD and longevity.